3a thread class right-hand 0.378" thread length flat countersunk head style 0.678" grip length 28 thread quantity per inch cadmium surface treated unjf thread series
3a thread class right-hand 0.444" thread length fillister countersunk head style 0.490" grip length 28 thread quantity per inch aluminum surface treated unjf thread series
3a thread class right-hand 0.408" thread length flat chamfer head style 32 thread quantity per inch passivate fastener surface treated unrc thread series